If A + B means A is the brother of B; A - B means A is the sister of B and A x B means A is the father of B. Which of the following means that C is the son of M?

'The only daughter of the father of X's mother' means mother of X.

Hence X is the son of the lady in the photograph.

Note: Still have doubt like "How X is a male?" - Let's see the discussions.

Nalni is the daughter of the only son of Gopi's grandfather. Hence, it's clear that Nalni is the sister of Gopi.

If D is Male, the answer is Nephew.

If D is Female, the answer is Niece.

As the sex of D is not known, hence, the relation between D and A cannot be determined.

Note: Niece - A daughter of one's brother or sister, or of one's brother-in-law or sister-in-law. Nephew - A son of one's brother or sister, or of one's brother-in-law or sister-in-law.

Ashok is the only brother of Sudeep and Veena is the sister-in-law of Ashok. Hence Veena is the wife of Sudeep. Kalyani is the mother-in-law of Veena. Kalyani is the mother of Ashok.

Madhav is the only son of one of the sons of Varman's father ? Either Varman is the father or uncle of Madhav.

A $ B ? A is the brother of B

B * C ? B is the son of C

Hence, ? A is the son of C

C @ D ? C is the wife of D

Hence, ? C is the mother of A.

Since E is the brother of B

Therefore, A is the father of E

but D is the wife of E.

Hence, D is the daughter-in-law of A.

Father of Deepak's daughter's father ? Deepak's father.

Hence, the person in the brother of Deepak's father.

Therefore, the person is the uncle of Deepak.